Door-lock



AM. PHOTO-LITRO. CD. NX (OSBURNE'S PROCESS.)

UNITED sTATEs PATENT oEEIoE.

THOMAS B. ATTERBURY, OF PITTSBURGH, PENNSYLVANIA.

Specification of Letters Patent No. 17,412, dated June 2, 1857.

To all whom 15 may concern:

Be it known that I, THOMAS B. ATTER- BURY, of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Door-Locks; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the annexed drawings, forming part of this specification, in which- Figure l, is a representation of my improved lock, the front plate being removed to exhibit the works in their position when the bolt is locked and dead-latched. Fig. 2, is a representation of my lock, similar to Fig. l, excepting the works are in the position they assume when the bolt is unlocked. Fig. 3, is a sectional representation of my lock, through the dotted line I to IV, Fig. l. Fig. 4, is a perspective view of the bolt and tumbler of my lock.

In the several figures like letters of refer ence denote similar parts.

The principal feature of my improve ment is the construction and arrangement of a single bolt in a lock answering the double purpose of a locking bolt and latch, so that when the bolt is unlocked, it is operated by the spindle of the knob, as a latch, and when locked by a key, it becomes de tached from the spindle which turns around without acting in any way on the bolt; and in connection therewith, the use of a stopper or dead-latch, acting, (not as usual, immediately on the locking bolt, but) on the tumbler of the bolt, so as not only to prevent the tumbler being raised, but also to prevent the key from coming in contact with the locking bolt, until the dead latch is thrown back. These features of my improvement not only add greatly to the security of the lock, but materially simplify, its construction making it much less liable to get out of repair, and much cheaper to manufacture.

To enable others, skilled in the art, to make and use my improved lock, I will proceed to describe its construction and operation.

` A, A is the lock case.

B is the bolt, the head of which project ing beyond the edge of the lock frame is beveled as an ordinary latch l bolt. This bolt has a single leg C, which works between the ways w, au projecting from the lock case, which keep the bolt in place as it slides backward and forward: the stop s preventing the bolt being thrown too far back.

Q, Q is the tumbler which is connected with the bolt B by a pin or pivot, b, on which it turns as a center. That portion of the tumbler, which lies back of the pivot b, I call the tumbler arm, which corresponds in shape with the leg C of the bolt, each of them having a projection (p on the leg of the bolt and 79 on the tumbler arm,) against which the radiating teeth d, d, d', of the follower D press, in operating the bolt B as a latch. That portion of the tumbler which is situate forward of the pivot b, and marked Q (the shape of which is shown more clearly in Fig. 4L) lies under the bolt, kand close to the inner surface of the front plate of the lock frame. The lower edge of the tumbler Q extends across the key notch 2', of the bolt, thus acting as a tumbler; since the point of the key cannot come in contact with the sides of the bolt in the key notch, until it has raised the tumbler, as will be seen by reference to Fig. l. The forward extremity of the tumbler Q is shaped like a hook, Z, which, when the tumbler is pressed down, and the bolt is unlocked, (as in Fig. 2) projects below the bolt, and presses against the rear side of a projection m from the lock case; thus preventing the bolt, when acting as a latch, from being thrown too far out of the lock frame, by its spring f; and the same hook Z, when the bolt is locked, (see Fig. 1,) preventing the bolt being pushed back by force applied from outside. On the upper edge of the tumbler Q is a shoulder which rises above the top of the bolt, and projects from the face of the tumbler, over the edge of the bolt, fitting into a suitable groove on the upper edge of the bolt B. This shoulder serves three purposes, `one in connection with the dead latch, hereafter explained; also as the bearing for the tumbler spring g; and, by projecting over the edge of the bolt, prevents the tumbler spring depressing the tumbler Q too much, or raising the arm Q j on the other side of the pivot b so high asto interfere with the action of the teeth 0l, d of the follower D. The tumbler spring g rides on the bolt B, being supported by a pin y (which is part of the bolt) one end resting on the shoulder of the tumbler Q, i

` tion p at the other end from the tooth d ofl bolt. The bolt spring f, presses against the head of the bolt B, when it acts as a latch; but when it is thrown forward, in locking, (as seen in Fig. 1,) the stop t prevents the spring f acting against the bolt; the necessity of a spring to give steadiness to the movement of the bolt in locking and unlocking, being obviated by the pressure of the spring tumbler Q on the point of the key. D is the follower which is turned in the usual manner by the spindle /c of the knob E. It is constructed in the usual manner, excepting that instead of two, it has three teeth CZ, CZ, rZ, radiating from the center of the follower, and equidistant from each other. Two of these teeth CZ, CZ rest against the projection p and p at the extremity of the leg of the bolt, and tumbler arm, when the bolt is unlocked (see Fig. and when the knob is turned either way, withdraw the bolt, which, when the handle or knob E .is released, springs back into its place; the action being the same as in ordinary latch bolts. The use of three teeth, instead of two, to the follower, renders a slighter turn of the handle sufficient to operate the latch bolt; but this is not the most important function of the three-teethed follower, as will be seen hereafter. The red lines in Fig. 2, indicate the position of the several parts of the lock when the spindle is turned to withdraw the bolt.

My lock as heretofore described, is simply a latch, excepting that the tumbler Q as such is unnecessary in that connection. I will now proceed to describe the operation of the parts when the bolt is used as a locking bolt: When the bolt is unlocked (as in Fig. 2) the key being inserted through the key hole, and turned as indicated by the arrow l, in Fig. 9., first comes in contact with that part of the lower edge of the tumbler, which crosses t-he key notchz' of the bolt B, wit-hout touching the bolt; the key raises the tumbler Q and depresses the tumbler arm Q on the other side of its pivot Z). This raises the hook Z from behind the projection m in the lock plate, and releases the projecthe follower D. There is then no obstacle in the way of the forward motion of the bolt B, which is accomplished by t-he action of the key, in the key notch z', the follower D being slightly turned by the projection p acting on the tooth eZ. As the key passes around out of the key notch z', the tumbler Q falls, by the reaction of its spring g; the hook Z passing over the projection m, and dropping 'down in front of it, thus preventing the retrocession of the bolt B, until the tumbler Q is again raised in unlocking the bolt. The bolt B will then have assumed the relative position with the followers D shownin Fig.

' 1. All the teeth d, eZ, (Z of the follower D being entirely out of the reach of t-he proj ections p, p at the extremity of the tumbler Q, and leg of the bolt C respectively. The spindle may then be turned around freely, but it has no effect, whatever on the bolt, or any of the works of the lock. The bolt being thus locked, can be further secured, so that even the key will not open it, by means of the dead latch F. This is a simple arm turning on a fixed point e, around which is a spiral spring n, pressing on the dead latch F, and on the lower plate of the lock, to cause it to retain any position in which it may be placed, and prevent the accidental fastening of the bolt. A thumb piece g projects upward, externally, through an open ing in the upper rim of the lock frame, and admits of the dead latch being adjusted from the inside of the door at pleasure. When the dead latch is in the position shown in Fig. l, the point of it rests on the shoulder' a: of the tumbler Q back of the spring r, and prevents the tumbler being raised, without which, it is obviously impossible to make the bolt even with the key, as the key has no purchase on the bolt, being prevented from touching it, as before described, until'the tumbler is raised; and as the bolt and tumbler both occupy all the space between the upper and lower plates of the lock frame, no instrument inserted through the key hole can reach the deadlatch, or relieve the tumbler of its influence.

If my lock is used as a mort-isc lock the thumb piece g to the dead-,latch is dispensed with, and instead of it, a slide is inserted from the inside of the door, entering a slot in the side of the lock frame, which moves t-he dead-latch backward and forward. It now remains to be shown how the tumbler arm Q and leg vof the bolt C engage them,- selves with the teeth CZ, CZ of the followerrD, when the door is unlocked. The dead lat-ch being thrown back, the key is turned in the direc-tion of the arrow l, in Fig. 1, and raising the tumbler in the key notch z' (to the position shown by the red lines in Fig. l) the hook Z rises from the projection m, in the lock plate, and allows the bolt B to pass backward, as the key presses against the side of the key notch c'. The tumbler arm Q, being lowered by the action of the key, on the under side of the tumbler Q, does not come in Contact with any of the teeth Z of the follower D; if the leg of the bolt C does, it pushes it back, causing the follower to turn. Then the bolt B is shot back, and the tumbler Q falls into its place by the reaction of its spring g, the tumbler arm Q rises to its normal position. Now if there were but two teeth (Z, cZ to the follower D, it might frequently happen that the teeth would be in such a position that they would not be brought to their proper place in front of the projections p', 79, without turning the spindle half around to adjust them, which would 17,412 fisl be very inconvenient, and might lead a person opening the door to suppose that it was locked, or that Ithe lock was out of order; but by having three teeth, one of them is sure to be within the range of the .tumbler arm Q or the leg of the bolt C, and another tooth d will likewise assume its position in front of the projection 7) at the end of the tumbler arm Q, at the slightest turn of the knob E to open the door; for the tooth fl', pressing against the end of the projection j), which is beveled for that purpose, overcomes the resistance of the spring g, sufficiently to press down the tumbler arm Q, and admit the tooth CZ of the follower D, to its proper position, when the parts of the lock will again have assumed the position shown in Fig. 2. This adjustment of the teeth of the follower in their relative position to the projections 7) p, is thus certainly effected, by turning the spindle no farther than is necessary to operate the latch in opening the door, and is done insensibly, which would not be the case if there were but two teeth to the follower.

Having thus described my improvement in locks, what I .claim as my invention, and desire to secure by Letters Patent, is

1. The use of the vibrating arm Q, Q, arranged and constructed as described, which while it acts as a tumbler ,to the bolt B, serves in combination with the follower D as a means of disconnecting the spindle from the bolt when the door is locked, and connecting them when unlocked as specified.

2. I do not claim the use of a dead latch operating directly on the locking bolt to prevent it being locked or unlocked by the key as that device is Well known, but what I do claim is the use of an arm or lever F which when pressing upon Vthe tumbler of the lock prevents its being raised, thus forming a guard which protects the locking bolt from any action of the key, and prevents the locking or unlocking of the bolt, in the manner substantially hereinbefore described.

In testimony whereof I have hereunto set my hand this tenth day of April A. D. 1857.

THOMAS B. ATTERBURY.

W'itnesses 1 AND. MoMasTER, THOMAS BORLAND. 

